Thyroid Support contains L-tyrosine, an amino acid that the thyroid uses to make its hormones. Seagreens ® Ascophyllum nodosum is the organic kelp (a type of seaweed) species that we use in our product. It provides a natural source of iodine – iodine is needed for thyroid hormone production and is one of the micronutrients known to be short in many people’s diets.